NAME
Devel::NYTProf::Apache - Profile mod_perl applications with Devel::NYTProf
SYNOPSIS
# in your Apache config file with mod_perl installed
PerlPassEnv NYTPROF
PerlModule Devel::NYTProf::Apache
If you're using virtual hosts with PerlOptions
that include either +Parent
or +Clone
then see "VIRTUAL HOSTS" below.
DESCRIPTION
This module allows mod_perl applications to be profiled using Devel::NYTProf
.
If the NYTPROF environment variable isn't set at the time Devel::NYTProf::Apache is loaded then Devel::NYTProf::Apache will issue a warning and default it to:
file=/tmp/nytprof.$$.out
The file actually created by NTProf will also have the process id appended to it because the addpid
option is enabled by default.
See "ENVIRONMENT VARIABLES" in Devel::NYTProf for more details on the settings effected by this environment variable. Try using PerlPassEnv
so you can set the NYTPROF environment variable externally.
Each profiled mod_perl process will need to have terminated before you can successfully read the profile data file. The simplest approach is to start the httpd, make some requests (e.g., 100 of the same request), then stop it and process the profile data.
Alternatively you could send a TERM signal to the httpd worker process to terminate that one process. The parent httpd process will start up another one for you ready for more profiling.
Example httpd.conf
It's often a good idea to use just one child process when profiling, which you can do by setting the MaxClients
to 1 in httpd.conf.
Using an IfDefine
blocks lets you leave the profile configuration in place and enable it whenever it's needed by adding -D NYTPROF
to the httpd startup command line.
<IfDefine NYTPROF>
MaxClients 1
PerlModule Devel::NYTProf::Apache
</IfDefine>
VIRTUAL HOSTS
If your httpd configuration includes virtual hosts with PerlOptions
that include either +Parent
or +Clone
then mod_perl2 will create a new perl interpreter to handle requests for that virtual host. This causes some issues for profiling.
If Devel::NYTProf::Apache
is loaded in the top-level configuration then activity in any virtual hosts that use their own perl interpreter won't be profiled. Normal virtual hosts will be profiled just fine.
You can profile a single virtual host that uses its own perl interpreter by loading Devel::NYTProf::Apache
inside the configuration for that virtual host. In this case do not use PerlModule
directive. You need to use a Perl
directive instead, like this:
<VirtualHost *:1234>
...
<Perl> use Devel::NYTProf::Apache; </Perl>
...
</VirtualHost>
LIMITATIONS
Profiling mod_perl on Windows is not supported because NYTProf currently doesn't support threads.
SEE ALSO
AUTHOR
Adam Kaplan, <akaplan at nytimes.com>
Tim Bunce, http://www.tim.bunce.name and http://blog.timbunce.org Steve Peters, <steve at fisharerojo.org>
COPYRIGHT AND LICENSE
Copyright (C) 2008 by Adam Kaplan and The New York Times Company.
Copyright (C) 2008 by Steve Peters.
Copyright (C) 2008 by Tim Bunce.
This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.8.8 or, at your option, any later version of Perl 5 you may have available.